Method of manufacturing electronic component

ABSTRACT

A method of manufacturing an electronic component includes preparing an unfired multilayer body including first and second main surfaces facing each other in a stacking direction, first and second side surfaces facing each other in a width direction, and first and second end surfaces facing each other in a length direction, bonding one side surface of each of unfired multilayer bodies to an adhesive sheet, polishing another side surface of each of the unfired multilayer bodies by rotating a polishing surface of a rotary polishing machine while contacting the another side surface, and forming a first insulating layer on the polished other side surface. In the polishing the another side surface, at least one of the rotary polishing machine and the adhesive sheet is moved relative to the other thereof to form a polish groove in the length direction.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority to Japanese PatentApplication No. 2019-092776 filed on May 16, 2019. The entire contentsof this application are hereby incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a method of manufacturing an electroniccomponent.

2. Description of the Related Art

Conventionally known is an electronic component formed by a plurality ofdielectric layers and a plurality of internal electrodes that arealternately stacked on one another, such as a multilayer ceramiccapacitor.

As one example of a method of manufacturing such an electroniccomponent, Japanese Patent Laid-Open No. 09-153433 discloses a method ofmanufacturing an electronic component in the following manner.Specifically, an unfired multilayer body is first fabricated, which isto be formed as a multilayer body after firing that includes a pluralityof dielectric layers and a plurality of internal electrodes alternatelystacked on one another so as to have both side surfaces from which theinternal electrodes are exposed. Then, an insulating layer is formed soas to cover the unfired internal electrodes exposed on both sidesurfaces of the unfired multilayer body, which is then subjected tofiring. Then, an external electrode is formed on each of both endsurfaces of the unfired multilayer body. Thereby, the electroniccomponent is manufactured. An unfired multilayer body can be fabricatedby cutting a stack of ceramic green sheets each having an internalelectrode pattern printed thereon.

In this case, there are minutely small projections and recesses on eachside surface of the unfired multilayer body obtained by cutting thestack of ceramic green sheets. Thus, if an insulating layer is formed inthis state, a gap occurs between the insulating layer and the unfiredmultilayer body, so that the insulating layer of the electroniccomponent is readily peeled off. Accordingly, it is preferable to reducesuch minutely small projections and recesses by polishing each sidesurface of the unfired multilayer body.

However, it turned out that, depending on the polishing method,polishing sag may occur in the unfired internal electrode exposed oneach side surface.

SUMMARY OF THE INVENTION

Preferred embodiments of the present invention provide methods ofmanufacturing an electronic component, by each of which the occurrenceof polishing sag in an unfired internal electrode is able to besignificantly reduced or prevented when a side surface of an unfiredmultilayer body is polished.

A method of manufacturing an electronic component according to apreferred embodiment of the present invention is to manufacture anelectronic component including at least a multilayer body and aninsulating layer that covers a side surface of the multilayer body. Themultilayer body includes a plurality of dielectric layers and aplurality of internal electrodes that are alternately stacked on oneanother. The method includes preparing an unfired multilayer body thatis to be formed as the multilayer body after firing, the unfiredmultilayer body including a first main surface and a second main surfacethat face each other in a stacking direction, a first side surface and asecond side surface that face each other in a width direction orthogonalor substantially orthogonal to the stacking direction, and a first endsurface and a second end surface that face each other in a lengthdirection orthogonal or substantially orthogonal to the stackingdirection and the width direction, bonding one side surface of the firstside surface and the second side surface of each of a plurality of theunfired multilayer bodies to an adhesive sheet, polishing another sidesurface of the first side surface and the second side surface of each ofthe unfired multilayer bodies by rotating a polishing surface of arotary polishing machine in a state where the polishing surface is incontact with the another side surface, and forming a first insulatinglayer on the polished other side surface. In the polishing the anotherside surface, at least one of the rotary polishing machine and theadhesive sheet is moved relative to the other of the rotary polishingmachine and the adhesive sheet to form a polish groove in the lengthdirection.

The unfired multilayer bodies may be bonded to the adhesive sheet to bespaced away from each other in a direction of relative movement betweenthe rotary polishing machine and the adhesive sheet, and a distancebetween the unfired multilayer bodies adjacent to each other issubstantially equal to or greater than a dimension of each of theunfired multilayer bodies in the stacking direction or in the lengthdirection.

The rotary polishing machine may have a cylindrical or substantiallycylindrical shape including an outer circumferential surface thatdefines and functions as a polishing surface.

The rotary polishing machine may have a cylindrical or substantiallycylindrical shape including two circular or substantially circularsurfaces that face each other. One of the two circular or substantiallycircular surfaces may define and function as a polishing surface.

A bank surrounding the unfired multilayer bodies may be provided on asurface of the adhesive sheet to which the unfired multilayer bodies arebonded. The bank has a height substantially equal to or greater than adimension of each of the unfired multilayer bodies in the widthdirection. Furthermore, at a corner portion of the bank, a gap may beprovided.

A magnet may be provided to attract the unfired multilayer bodies peeledoff from the adhesive sheet by polishing.

Each of the internal electrodes may include Ni.

According to methods of manufacturing an electronic component accordingto preferred embodiments of the present invention, at least one of therotary polishing machine and the adhesive sheet is moved relative to theother of the rotary polishing machine and the adhesive sheet to form apolish groove on the unfired multilayer body in its length direction.Thus, by aligning the extending direction of each unfired internalelectrode exposed on the another side surface of the unfired multilayerbody to extend in the same or substantially the same direction as thedirection in which a polish groove is formed, the occurrence ofpolishing sag in each unfired internal electrode is able to besignificantly reduced or prevented.

The above and other elements, features, steps, characteristics andadvantages of the present invention will become more apparent from thefollowing detailed description of the preferred embodiments withreference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a multilayer ceramic capacitor asan example of an electronic component.

FIG. 2 is a view of the multilayer ceramic capacitor shown in FIG. 1 ina cross section taken along a line II-II.

FIG. 3 is a view of the multilayer ceramic capacitor shown in FIG. 1 ina cross section taken along a line III-III.

FIG. 4 is a perspective view of a multilayer body forming the multilayerceramic capacitor.

FIG. 5 is a flowchart showing an example of the steps of manufacturing amultilayer ceramic capacitor according to a preferred embodiment of thepresent invention.

FIG. 6 is a perspective view of an unfired multilayer body.

FIG. 7 is a plan view showing the state where the second side surface asone side surface of each of a plurality of unfired multilayer bodies isbonded to the first adhesive sheet.

FIG. 8 is a side view showing an unfired multilayer body and a bank thatare bonded to the first adhesive sheet.

FIG. 9 is a diagram showing the state where a rotary polishing machinepolishes the first side surfaces as the other side surfaces of theunfired multilayer bodies.

FIG. 10 is a diagram showing the extending direction of a polish groovethat is provided on the first side surface as the other side surface ofeach unfired multilayer body during polishing by the rotary polishingmachine.

FIG. 11 is a perspective view showing the state where another rotarypolishing machine polishes the first side surfaces as the other sidesurfaces of the plurality of unfired multilayer bodies.

FIG. 12 is a top view showing the positional relation between the rotarypolishing machine and the plurality of unfired multilayer bodies.

FIG. 13 is a side view showing the plurality of unfired multilayerbodies bonded to the first adhesive sheet, the rotary polishing machine,and a magnet.

FIG. 14 is a diagram showing the state where the unfired multilayerbodies on the first insulating sheet having the second adhesive sheetbonded thereto are peeled off from the first adhesive sheet.

FIGS. 15A and 15B each are a diagram showing an example of a method ofcutting the first insulating sheet and the second insulating sheet toseparate the unfired multilayer bodies from each other.

FIGS. 16A and 16B each are a diagram showing another method of cuttingthe first insulating sheet and the second insulating sheet to separatethe unfired multilayer bodies from each other.

FIG. 17 is a plan view showing a plurality of unfired multilayer bodiesbonded to the first adhesive sheet in a direction different by about 90°from the direction of unfired multilayer bodies shown in FIG. 7.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will be hereinafterdescribed to specifically explain the features of the present invention.In the following, a multilayer ceramic capacitor will be described as anexample of an electronic component to be manufactured. It should benoted that the electronic component only has to include at least amultilayer body including a plurality of dielectric layers and aplurality of internal electrodes that are alternately stacked on oneanother, and an insulating layer that covers the side surface of themultilayer body, but is not limited to such a multilayer ceramiccapacitor.

Multilayer Ceramic Capacitor

FIG. 1 is a perspective view showing a multilayer ceramic capacitor 10as an example of an electronic component. FIG. 2 is a view of multilayerceramic capacitor 10 shown in FIG. 1 in a cross section taken along aline II-II. FIG. 3 is a view of multilayer ceramic capacitor 10 shown inFIG. 1 in a cross section taken along a line FIG. 4 is a perspectiveview of a multilayer body 11 forming multilayer ceramic capacitor 10.

As shown in FIGS. 1 to 3, multilayer ceramic capacitor 10 has arectangular parallelepiped or substantially rectangular parallelepipedshape, and includes a multilayer body 11, a first insulating layer 12, asecond insulating layer 13, a first external electrode 14 a, and asecond external electrode 14 b. First external electrode 14 a and secondexternal electrode 14 b face each other as shown in FIG. 1.

Accordingly, the direction in which first external electrode 14 a andsecond external electrode 14 b face each other is defined as a lengthdirection L of multilayer ceramic capacitor 10. The direction in which afirst internal electrode 15 a and a second internal electrode 15 b(described herein) are stacked on each other is defined as a stackingdirection T. The direction orthogonal or substantially orthogonal toeach of length direction L and stacking direction T is defined as awidth direction W. As shown in FIG. 1, length direction L is orthogonalor substantially orthogonal to stacking direction T and width directionW.

Multilayer ceramic capacitor 10 includes a corner portion and aridgeline portion, each of which is rounded. The corner portion is aportion at which three planes of multilayer ceramic capacitor 10 crosseach other. The ridgeline portion is a portion at which two planes ofmultilayer ceramic capacitor 10 cross each other.

As shown in FIG. 4, multilayer body 11 includes a first end surface 17 aand a second end surface 17 b that face each other in length directionL, a first main surface 18 a and a second main surface 18 b that faceeach other in stacking direction T, and a first side surface 19 a and asecond side surface 19 b that face each other in width direction W.

First end surface 17 a and second end surface 17 b extend in widthdirection W and stacking direction T. First main surface 18 a and secondmain surface 18 b extend in length direction L and width direction W.First side surface 19 a and second side surface 19 b extend in lengthdirection L and stacking direction T.

As shown in FIGS. 2 and 3, multilayer body 11 includes an inner layerportion 21 and an outer layer portion 22.

Inner layer portion 21 includes internal electrodes 15 a, 15 b and adielectric layer 16. The internal electrodes include a first internalelectrode 15 a and a second internal electrode 15 b. Dielectric layer 16is sandwiched between first internal electrode 15 a and second internalelectrode 15 b. A plurality of first internal electrodes 15 a and aplurality of second internal electrodes 15 b are alternately stacked onone another with dielectric layer 16 interposed between the plurality offirst internal electrodes 15 a and the plurality of second internalelectrodes 15 b, to thus define inner layer portion 21.

First internal electrode 15 a and second internal electrode 15 b faceeach other in stacking direction T with dielectric layer 16 interposedbetween the plurality of first internal electrodes 15 a and theplurality of second internal electrodes 15 b. Capacitance occurs by theportion where first internal electrode 15 a and second internalelectrode 15 b face each other with dielectric layer 16 interposedprovided between the plurality of first internal electrodes 15 a and theplurality of second internal electrodes 15 b.

Dielectric layer 16 includes a plurality of crystalline particles eachpreferably including Ba and Ti, and each having a perovskite-typestructure, for example.

Dielectric layer 16 extends in width direction W and length direction L.First internal electrode 15 a has a flat plate shape along dielectriclayer 16 and extends to first end surface 17 a of multilayer body 11.Second internal electrode 15 b has a flat plate shape along dielectriclayer 16 and extend to second end surface 17 b of multilayer body 11.

Furthermore, first internal electrode 15 a and second internal electrode15 b are exposed at each of first side surface 19 a and second sidesurface 19 b of multilayer body 11.

First internal electrode 15 a and second internal electrode 15 b eachpreferably include Ni, for example. In addition to Ni, first internalelectrode 15 a and second internal electrode 15 b each may include metalsuch as Cu, Ag, Pd, an Ag—Pd alloy, and Au, for example. Furthermore,first internal electrode 15 a and second internal electrode 15 b eachmay include the same or similar dielectric particles as those ofdielectric layer 16.

Outer layer portion 22 is provided on both sides of inner layer portion21 in stacking direction T, and more specifically, provided on bothsides of the internal electrodes in stacking direction T that arelocated on both outermost sides in stacking direction T among theplurality of first internal electrodes 15 a and the plurality of secondinternal electrodes 15 b. In other words, inner layer portion 21 issandwiched between two outer layer portions 22 provided on both outsidesin stacking direction T. Outer layer portion 22 is a region in whichfirst internal electrode 15 a and second internal electrode 15 b are notprovided in a view, seen in length direction L, of an optional crosssection of multilayer body 11 that extends in stacking direction T andwidth direction W. Outer layer portion 22 preferably includes the sameor similar material as that of dielectric layer 16, for example.

First insulating layer 12 is in contact with first side surface 19 a ofmultilayer body 11 to cover first side surface 19 a. Second insulatinglayer 13 is in contact with second side surface 19 b of multilayer body11 to cover second side surface 19 b. In other words, multilayer body 11is sandwiched between first insulating layer 12 and second insulatinglayer 13 from both sides in width direction W.

As described below, first insulating layer 12 and second insulatinglayer 13 each preferably have a two-layer structure. However, firstinsulating layer 12 and second insulating layer 13 each may includethree or more layers or may include one layer. Furthermore, the materialof each of first insulating layer 12 and second insulating layer 13 maybe the same as or different from that of dielectric layer 16.

As shown in FIG. 1, first external electrode 14 a is provided over theentire or substantially the entire first end surface 17 a of multilayerbody 11 and over the entire or substantially the entire ends of firstinsulating layer 12 and second insulating layer 13 on the first endsurface 17 a side, and extends therefrom partially over both outsides instacking direction T and both outsides in width direction W. Firstexternal electrode 14 a is electrically connected to first internalelectrode 15 a.

As shown in FIG. 1, second external electrode 14 b is provided over theentire or substantially the entire second end surface 17 b of multilayerbody 11 and over the entire or substantially the entire ends of firstinsulating layer 12 and second insulating layer 13 on the second endsurface 17 b side, and extends therefrom partially over both outsides instacking direction T and both outsides in width direction W. Secondexternal electrode 14 b is electrically connected to second internalelectrode 15 b.

First external electrode 14 a and second external electrode 14 b eachinclude an underlying electrode layer and a plated layer that isprovided on the underlying electrode layer, for example.

The underlying electrode layer preferably includes at least one oflayers as a baked electrode layer, a resin electrode layer, and a thinelectrode layer, for example, as will be described below.

The baked electrode layer may include glass and metal, and may includeone layer or two or more layers. The baked electrode layer preferablyincludes metal such as Cu, Ni, Ag, Pd, and Au, or an alloy of Ag and Pd,for example.

The baked electrode layer is formed by baking a multilayer body to whichan electrically conductive paste including glass and metal has beenapplied. Baking may be performed simultaneously or substantiallysimultaneously with firing of the unfired multilayer body or may beperformed after firing of the unfired multilayer body.

The resin electrode layer may be formed as a layer includingelectrically conductive particles and a thermosetting resin, forexample. When the resin electrode layer is provided, the resin electrodelayer may be provided directly on the multilayer body without providinga baked electrode layer. The number of resin electrode layers may be oneor may be more than one.

The thin electrode layer is a layer formed by deposition of metalparticles and preferably having a thickness of 1 μm or less, forexample. The thin electrode layer may be formed by known thin-filmforming methods, for example, a sputtering method or an evaporationmethod.

The plated layer provided on the underlying electrode layer preferablyincludes at least one of metal such as Cu, Ni, Ag, Pd, and Au, or analloy of Ag and Pd, for example. The number of plated layers may be oneor may be more than one. The plated layer preferably includes atwo-layer structure including an Ni-plated layer and an Sn-plated layer,for example. The Ni-plated layer significantly reduces or prevents theunderlying electrode layer from being eroded by the solder to mountmultilayer ceramic capacitor 10. The Sn-plated layer significantlyincreases the wettability of the solder that mounts multilayer ceramiccapacitor 10. [006U] First external electrode 14 a and second externalelectrode 14 b do not have to include the above-described underlyingelectrode layer, but may include a plated layer that is to be directlyprovided on multilayer body 11. Accordingly, the plated layer isdirectly connected to first internal electrode 15 a or second internalelectrode 15 b.

Method of Manufacturing Multilayer Ceramic Capacitor

The following is an explanation of an example of a method ofmanufacturing multilayer ceramic capacitor 10 having the above-describedstructure. FIG. 5 is a flowchart showing an example of the steps ofmanufacturing multilayer ceramic capacitor 10 according to a preferredembodiment of the present invention.

In step S1 in FIG. 5, an unfired multilayer body that is to be formed asmultilayer body 11 after firing is prepared. The unfired multilayer bodymay be prepared in advance or may be produced by conventionally knownmethods. For example, a plurality of ceramic green sheets each includingan electrically conductive paste for internal electrodes applied theretoare stacked on one another and cut into pieces each having a prescribedsize. Thus, an unfired multilayer body is able to be produced.

FIG. 6 is a perspective view of an unfired multilayer body 110. Unfiredmultilayer body 110 includes a first main surface 180 a and a secondmain surface 180 b that face each other in stacking direction T; a firstside surface 190 a and a second side surface 190 b that face each otherin width direction W orthogonal or substantially orthogonal to stackingdirection T; and a first end surface 170 a and a second end surface 170b that face each other in length direction L orthogonal or substantiallyorthogonal to stacking direction T and width direction W.

At first end surface 170 a of unfired multilayer body 110, the firstinternal electrode before firing (that is, a first unfired internalelectrode 150 a) is exposed. At second end surface 170 b of unfiredmultilayer body 110, the second internal electrode before firing (thatis, a second unfired internal electrode 150 b) is exposed. Also, firstunfired internal electrode 150 a and second unfired internal electrode150 b are exposed at each of first side surface 190 a and second sidesurface 190 b of unfired multilayer body 110.

In step S2 after step S1, one side surface of first side surface 190 aand second side surface 190 b of each unfired multilayer body 110 isbonded to the first adhesive sheet. In the following description, oneside surface of first side surface 190 a and second side surface 190 bis defined as second side surface 190 b while the other side surface offirst side surface 190 a and second side surface 190 b is defined asfirst side surface 190 a, but one side surface may be defined as firstside surface 190 a while the other side surface may be defined as secondside surface 190 b.

The method of bonding second side surface 190 b as one side surface ofeach of the plurality of unfired multilayer bodies 110 to the firstadhesive sheet is not particularly limited.

FIG. 7 is a diagram showing the state where second side surface 190 b asone side surface of each of the plurality of unfired multilayer bodies110 is bonded to first adhesive sheet 31. In this state, first sidesurface 190 a as the other side surface of each unfired multilayer body110 is exposed.

In the present preferred embodiment, first adhesive sheet 31 isdescribed as having an elongated shape without limitation. Furthermore,any number of unfired multilayer bodies 110 may be bonded to firstadhesive sheet 31.

As shown in FIG. 7, a plurality of unfired multilayer bodies 110 arebonded in a matrix configuration to first adhesive sheet 31. In thepresent preferred embodiment, a distance L0 between two unfiredmultilayer bodies 110 located adjacent to each other in length directionL of unfired multilayer body 110 is substantially equal to or greaterthan the dimension of unfired multilayer body 110 in length direction L.Also, a distance TO between two unfired multilayer bodies 110 locatedadjacent to each other in stacking direction T of unfired multilayerbody 110 is substantially equal to or greater than the dimension ofunfired multilayer body 110 in stacking direction T.

However, distance L0 between two unfired multilayer bodies 110 locatedadjacent to each other in length direction L of unfired multilayer body110 may be less than the dimension of unfired multilayer body 110 inlength direction L. Furthermore, distance TO between two unfiredmultilayer bodies 110 located adjacent to each other in stackingdirection T of unfired multilayer body 110 may be less than thedimension of unfired multilayer body 110 in stacking direction T.

Furthermore, in the present preferred embodiment, a bank 40 surroundingthe plurality of unfired multilayer bodies 110 is provided on thesurface of first adhesive sheet 31 to which unfired multilayer bodies110 are bonded. Bank 40 is formed to have a height substantially equalto or greater than the dimension of each unfired multilayer body 110 inwidth direction W. FIG. 8 is a side view showing unfired multilayer body110 and bank 40 that are bonded to first adhesive sheet 31. In FIG. 8,the height of bank 40 is greater than the dimension of unfiredmultilayer body 110 in width direction W, but may be the same orsubstantially the same as the dimension of unfired multilayer body 110in width direction W. In addition, the height of bank 40 means thedimension of bank 40 in the direction orthogonal or substantiallyorthogonal to the main surface of first adhesive sheet 31. The cornerportion of bank 40 is preferably provided with, for example, a gap,through which a polishing solution flows in.

As will be described herein, a rotary polishing machine polishes theother side surface of unfired multilayer body 110. Accordingly,polishing impact causes a strong flow of the polishing solution. Due tothis flow of the polishing solution, unfired multilayer body 110 maypeel off and fly away from first adhesive sheet 31. However, with bank40 provided to surround the plurality of unfired multilayer bodies 110,an excessive flow of the polishing solution is able to be significantlyreduced or prevented, dispersion of unfired multilayer bodies 110 thatfly away during polishing is able to be significantly reduced orprevented, and also, unfired multilayer bodies 110 that fly away areable to be readily collected.

In step S3 after step S2 in FIG. 5, the polishing surface of the rotarypolishing machine is rotated while being in contact with the other sidesurface of first side surface 190 a and second side surface 190 b ofeach unfired multilayer body 110, to polish the other side surface ofeach unfired multilayer body 110. In other words, in the state where oneside surface is bonded to the adhesive sheet, the other side surface isexposed, and therefore, polished.

FIG. 9 is a diagram showing the state where a rotary polishing machine50 polishes first side surfaces 190 a as the other side surfaces ofunfired multilayer bodies 110. It should be noted that FIG. 9 does notshow bank 40 on first adhesive sheet 31.

Rotary polishing machine 50 has a cylindrical or substantiallycylindrical shape including two circular or substantially circularsurfaces 50 a, 50 b and an outer circumferential surface 50 c that islocated between two circular or substantially circular surfaces 50 a and50 b. Outer circumferential surface 50 c defines and functions as apolishing surface. When polishing first side surface 190 a of unfiredmultilayer body 110, outer circumferential surface 50 c is rotated inthe state where this outer circumferential surface 50 c is in contactwith first side surface 190 a of unfired multilayer body 110, to thuspolish first side surface 190 a. As shown in FIG. 7, a plurality ofunfired multilayer bodies 110 are bonded onto first adhesive sheet 31 instacking direction T of each of unfired multilayer bodies 110. Thus,first side surfaces 190 a of the plurality of unfired multilayer bodies110 provided in rows are able to be simultaneously or substantiallysimultaneously polished.

Accordingly, during polishing by rotary polishing machine 50, at leastone of rotary polishing machine 50 and first adhesive sheet 31 is movedrelative to the other of rotary polishing machine 50 and first adhesivesheet 31, and a polish groove is formed in length direction L on theside surface of each unfired multilayer body 110 with which thepolishing surface comes into contact. The polish groove is formed in thedirection in which the polishing surface of rotary polishing machine 50moves relative to the other side surface of each unfired multilayer body110. Accordingly, at least one of rotary polishing machine 50 and firstadhesive sheet 31 is moved relative to the other of rotary polishingmachine 50 and first adhesive sheet 31 in length direction L of eachunfired multilayer body 110. A polishing solution is preferablyintroduced during polishing, for example.

In a polishing example shown in FIG. 9, the tangent line of outercircumferential surface 50 c in its rotation direction extends in thesame or substantially the same direction as length direction L ofunfired multilayer body 110 at a contact position between first sidesurface 190 a as the other side surface of unfired multilayer body 110and outer circumferential surface 50 c as a polishing surface of rotarypolishing machine 50. In this state, when first adhesive sheet 31 ismoved in the direction indicated by an arrow Y1 in which the pluralityof unfired multilayer bodies 110 approach rotary polishing machine 50,or when first adhesive sheet 31 is moved in the direction indicated byan arrow Y2 in which rotary polishing machine 50 approaches theplurality of unfired multilayer bodies 110, a polish groove is formed inlength direction L on the side surface of each of unfired multilayerbodies 110. Also, first adhesive sheet 31 may be moved in the directionindicated by arrow Y1 and rotary polishing machine 50 may be moved inthe direction indicated by arrow Y2.

FIG. 10 is a diagram showing an extending direction S of the polishgroove that is provided on first side surface 190 a as the other sidesurface of each unfired multilayer body 110 during polishing by rotarypolishing machine 50. As shown in FIG. 10, extending direction S of thepolish groove formed on first side surface 190 a of unfired multilayerbody 110 extends in the same or substantially the same direction aslength direction L of unfired multilayer body 110. In other words, byaligning extending direction S of the polish groove formed on first sidesurface 190 a of unfired multilayer body 110 to extend in the same orsubstantially the same direction as the extending direction of each offirst unfired internal electrode 150 a and second unfired internalelectrode 150 b that are exposed at first side surface 190 a, occurrenceof polishing sag in first unfired internal electrode 150 a and secondunfired internal electrode 150 b is able to be significantly reduced orprevented.

On the other hand, at least one of rotary polishing machine 50 and firstadhesive sheet 31 is moved relative to the other of rotary polishingmachine 50 and first adhesive sheet 31, and extending direction S of thepolish groove formed on the other side surface of unfired multilayerbody 110 is orthogonal or substantially orthogonal to length direction Lof unfired multilayer body 110 (that is, the extending direction of eachof first unfired internal electrode 150 a and second unfired internalelectrode 150 b that are exposed). As a result, polishing sag is morelikely to occur in first unfired internal electrode 150 a and secondunfired internal electrode 150 b.

FIG. 11 is a perspective view showing the state where another rotarypolishing machine 51 polishes first side surfaces 190 a as the otherside surfaces of the plurality of unfired multilayer bodies 110. FIG. 12is a top view showing the positional relation between rotary polishingmachine 51 and the plurality of unfired multilayer bodies 110.

Rotary polishing machine 51 shown in FIGS. 11 and 12 has a cylindricalor substantially cylindrical shape including two circular orsubstantially circular surfaces 51 a and 51 b that face each other.Accordingly, surface 51 a defines and functions as a polishing surface.

In addition, during polishing by rotary polishing machine 51, at leastone of rotary polishing machine 51 and first adhesive sheet 31 is movedrelative to the other of rotary polishing machine 51 and first adhesivesheet 31, and a polish groove is formed in length direction L on theside surface of each unfired multilayer body 110 with which thepolishing surface comes into contact.

Each unfired multilayer body 110 is polished at the position where therotation direction of the polishing surface extends in the same orsubstantially the same direction as length direction L of each unfiredmultilayer body 110. In other words, each unfired multilayer body 110 ispolished at the position located as close as possible to a position P1at which the direction of a tangent line 510 of circular orsubstantially circular surface 51 a as the polishing surface of rotarypolishing machine 51 extends in the same or substantially the samedirection as length direction L of unfired multilayer body 110. Bypolishing each unfired multilayer body 110 at such a position, a polishgroove is formed in length direction L on the side surface of eachunfired multilayer body 110 with which the polishing surface comes intocontact. In order to polish the plurality of unfired multilayer bodies110 bonded to first adhesive sheet 31, first adhesive sheet 31 may bemoved in the direction indicated by an arrow Y1 in FIG. 12 or rotarypolishing machine 51 may be moved in the direction indicated by an arrowY2 in FIG. 12. Also, first adhesive sheet 31 may be moved in thedirection indicated by arrow Y1 and rotary polishing machine 51 may bemoved in the direction indicated by arrow Y2.

For polishing, the extending direction of the polish groove formed onthe other side surface of each unfired multilayer body 110 and lengthdirection L do not necessarily extend completely in the same orsubstantially the same direction, but may extend approximately in thesame or substantially the same direction.

In the present preferred embodiment, as shown in FIG. 13, a magnet 60 isprovided to attract unfired multilayer body 110 that is peeled off fromfirst adhesive sheet 31 due to polishing by rotary polishing machine 50.In the case where first adhesive sheet 31 is conveyed in the directionindicated by an arrow Y1 in FIG. 13, the side on which unfiredmultilayer body 110 before polishing is located is defined as anupstream side while the side on which unfired multilayer body 110 afterpolishing is located is defined as a downstream side. Accordingly,magnet 60 is preferably located on the downstream side, for example.First unfired internal electrode 150 a and second unfired internalelectrode 150 b each preferably including Ni, for example, are exposedon each of first side surface 190 a and second side surface 190 b ofunfired multilayer body 110. Thus, unfired multilayer body 110 flownaway due to impact during polishing are able to be attracted to magnet60. Thereby, unfired multilayer bodies 110 flown away during polishingis able to be significantly reduced or prevented from dispersing and areable to be readily collected.

The same or similar features and advantageous effects are applicablealso to the case where rotary polishing machine 50 shown in FIG. 10 isused in place of rotary polishing machine 50 shown in FIG. 9.

In step S4 after step S3 in FIG. 5, the first insulating sheet isaffixed onto the polished other side surface of each unfired multilayerbody 110 in order to form the first insulating layer. Accordingly, onefirst insulating sheet is affixed to cover the other side surfaces ofthe plurality of unfired multilayer bodies 110.

In step S5 after step S4 in FIG. 5, the second adhesive sheet is firstbonded to the first insulating sheet, and then, first adhesive sheet 31is peeled off. The second adhesive sheet is preferably higher inadhesive strength than first adhesive sheet 31, for example. FIG. 14 isa diagram showing the state where unfired multilayer bodies 110 on firstinsulating sheet 61 having second adhesive sheet 32 bonded thereto arepeeled off from first adhesive sheet 31.

The method of peeling off unfired multilayer bodies 110 from firstadhesive sheet 31 is not limited to the above-described method. Theadhesive strength of first adhesive sheet 31 may be weakened before thefirst adhesive sheet is peeled off. For example, when first adhesivesheet 31 includes the material having adhesive strength that is weakenedby heating, first adhesive sheet 31 is heated. When first adhesive sheet31 includes the material having adhesive strength that is weakened byultraviolet irradiation, first adhesive sheet 31 is irradiated withultraviolet rays.

Step S6 after step S5 in FIG. 5 includes polishing one side surfaces ofunfired multilayer bodies 110 that are exposed as a result of peelingoff of first adhesive sheet 31. Second side surface 190 b as one sidesurface is polished by the method similar to the method to polish firstside surface 190 a as the other side surface. In other words, at leastone of the rotary polishing machine and second adhesive sheet 32 ismoved relative to the other of the rotary polishing machine and secondadhesive sheet 32 that polishes, and a polish groove is formed in lengthdirection L on one side surface of unfired multilayer body 110. Thereby,occurrence of polishing sag is able to be significantly reduced orprevented in first unfired internal electrode 150 a and second unfiredinternal electrode 150 b also on one side surface of each unfiredmultilayer body 110.

In step S7 after step S6 in FIG. 5, the second insulating sheet isaffixed onto the polished one side surface of each unfired multilayerbody 110 in order to form the second insulating layer. Accordingly, onesecond insulating sheet is affixed to cover one side surfaces of theplurality of unfired multilayer bodies 110.

In step S8 after step S7, first insulating sheet 61 and secondinsulating sheet 62 are cut to separate unfired multilayer bodies 110from each other. Specifically, in the state where one first insulatingsheet 61 is affixed onto the other side surfaces of the plurality ofunfired multilayer bodies 110 and one second insulating sheet 62 isaffixed onto one side surfaces of the plurality of unfired multilayerbodies 110, pressing force is applied from outside first insulatingsheet 61 and second insulating sheet 62 to unfired multilayer bodies110. Thereby, first insulating sheet 61 and second insulating sheet 62are cut to separate unfired multilayer bodies 110 from each other.

FIGS. 15A and 15B each are a diagram showing an example of a method ofcutting first insulating sheet 61 and second insulating sheet 62 toseparate unfired multilayer bodies 110 from each other. As shown in FIG.15A, first insulating sheet 61, unfired multilayer bodies 110 and secondinsulating sheet 62 are sandwiched between a pair of rollers 70 a and 70b. In this state, while rotating the pair of rollers 70 a and 70 b,pressing force is applied to unfired multilayer bodies 110 from outsidefirst insulating sheet 61 and second insulating sheet 62.

Accordingly, shear force is applied to each of first insulating sheet 61and second insulating sheet 62 between the region in contact withunfired multilayer body 110 and the region not in contact with unfiredmultilayer body 110. By this shear force, first insulating sheet 61 andsecond insulating sheet 62 are cut between the region in contact withunfired multilayer body 110 and the region not in contact with unfiredmultilayer body 110, as shown in FIG. 15B.

FIGS. 16A and 16B each are a diagram showing another method of cuttingfirst insulating sheet 61 and second insulating sheet 62 to separateunfired multilayer bodies 110 from each other. As shown in FIG. 16A,first insulating sheet 61, unfired multilayer bodies 110 and secondinsulating sheet 62 are sandwiched between a pair of pressing elements80 a and 80 b. The surfaces of pressing elements 80 a and 80 b that comeinto contact with at least first insulating sheet 61 or secondinsulating sheet 62 preferably include an elastic body, for example,rubber.

In the state where first insulating sheet 61, unfired multilayer bodies110 and second insulating sheet 62 are sandwiched between the pair ofpressing elements 80 a and 80 b, pressing force is applied to unfiredmultilayer bodies 110 from outside first insulating sheet 61 and secondinsulating sheet 62. Thus, shear force is applied to first insulatingsheet 61 and second insulating sheet 62 between the region in contactwith each unfired multilayer body 110 and the region not in contact witheach unfired multilayer body 110. Thus, first insulating sheet 61 andsecond insulating sheet 62 are cut to separate unfired multilayer bodies110 from each other as shown in FIG. 16B.

In step S9 after step S8 in FIG. 5, a structure body of unfiredmultilayer body 110 is fired that includes first side surface 190 a towhich the cut first insulating sheet 61 is affixed, and second sidesurface 190 b to which the cut second insulating sheet 62 is affixed. Byfiring, unfired multilayer body 110 is formed into multilayer body 11,the cut first insulating sheet 61 is formed into first insulating layer12, and the cut second insulating sheet 62 is formed into secondinsulating layer 13.

In step S10 after step S9, first external electrode 14 a and secondexternal electrode 14 b are formed. Also, after applying an externalelectrode paste to unfired multilayer body 110 having the cut firstinsulating sheet 61 and the cut second insulating sheet 62 affixedthereto, the resultant may be simultaneously or substantiallysimultaneously fired.

Thus, multilayer ceramic capacitor 10 is provided by the above-describedmanufacturing steps.

The present invention is not limited to the above-described preferredembodiments, but may be variously applicable and modifiable in the scopeof the present invention.

For example, unfired multilayer body 110 may be bonded to first adhesivesheet 31 in the direction different from the direction of unfiredmultilayer body 110 shown in FIG. 7. FIG. 17 is a diagram showing aplurality of unfired multilayer bodies 110 bonded to first adhesivesheet 31 in the direction different by about 90° from the direction ofunfired multilayer bodies 110 shown in FIG. 7.

Also in the case where each of unfired multilayer bodies 110 is bondedto first adhesive sheet 31 in the direction shown in FIG. 17, distanceL0 between two unfired multilayer bodies 110 located adjacent to eachother in length direction L of each unfired multilayer body 110 issubstantially equal to or greater than the dimension of each unfiredmultilayer body 110 in length direction L. Also, distance TO between twounfired multilayer bodies 110 located adjacent to each other in stackingdirection T of each unfired multilayer body 110 is substantially equalto or greater than the dimension of each unfired multilayer body 110 instacking direction T. It should be noted that distance L0 between twounfired multilayer bodies 110 located adjacent to each other in lengthdirection L of each unfired multilayer body 110 may be less than thedimension of each unfired multilayer body 110 in length direction L.Furthermore, distance TO between two unfired multilayer bodies 110located adjacent to each other in stacking direction T of each unfiredmultilayer body 110 may be less than the dimension of each unfiredmultilayer body 110 in stacking direction T.

While preferred embodiments of the present invention have been describedabove, it is to be understood that variations and modifications will beapparent to those skilled in the art without departing from the scopeand spirit of the present invention. The scope of the present invention,therefore, is to be determined solely by the following claims.

What is claimed is:
 1. A method of manufacturing an electronic componentincluding at least a multilayer body and an insulating layer that coversa side surface of the multilayer body, the multilayer body including aplurality of dielectric layers and a plurality of internal electrodesthat are alternately stacked on one another, the method comprising:preparing an unfired multilayer body that is to be formed as themultilayer body after firing, the unfired multilayer body including: afirst main surface and a second main surface that face each other in astacking direction; a first side surface and a second side surface thatface each other in a width direction orthogonal or substantiallyorthogonal to the stacking direction; and a first end surface and asecond end surface that face each other in a length direction orthogonalor substantially orthogonal to the stacking direction and the widthdirection; bonding one side surface of the first side surface and thesecond side surface of each of a plurality of the unfired multilayerbodies to an adhesive sheet; polishing another side surface of the firstside surface and the second side surface of each of the unfiredmultilayer bodies by rotating a polishing surface of a rotary polishingmachine in a state where the polishing surface is in contact with theanother side surface; and forming a first insulating layer on thepolished other side surface; wherein in the polishing the another sidesurface, at least one of the rotary polishing machine and the adhesivesheet is moved relative to the other of the rotary polishing machine andthe adhesive sheet to form a polish groove in the length direction. 2.The method of manufacturing an electronic component according to claim1, wherein the unfired multilayer bodies are bonded to the adhesivesheet to be spaced away from each other in a direction of relativemovement between the rotary polishing machine and the adhesive sheet;and a distance between the unfired multilayer bodies adjacent to eachother is substantially equal to or greater than a dimension of each ofthe unfired multilayer bodies in the stacking direction or in the lengthdirection.
 3. The method of manufacturing an electronic componentaccording to claim 1, wherein the rotary polishing machine has acylindrical or substantially cylindrical shape including an outercircumferential surface that defines and functions as a polishingsurface.
 4. The method of manufacturing an electronic componentaccording to claim 1, wherein the rotary polishing machine has acylindrical or substantially cylindrical shape including two circular orsubstantially circular surfaces that face each other, and one of the twocircular or substantially circular surfaces defines and functions as apolishing surface.
 5. The method of manufacturing an electroniccomponent according to claim 1, wherein a bank surrounding the unfiredmultilayer bodies is provided on a surface of the adhesive sheet towhich the unfired multilayer bodies are bonded; and the bank has aheight substantially equal to or greater than a dimension of each of theunfired multilayer bodies in the width direction.
 6. The method ofmanufacturing an electronic component according to claim 1, wherein amagnet is provided to attract the unfired multilayer bodies peeled offfrom the adhesive sheet by polishing.
 7. The method of manufacturing anelectronic component according to claim 1, wherein each of the pluralityof internal electrodes includes Ni.
 8. The method of manufacturing anelectronic component according to claim 7, wherein each of the pluralityof internal electrodes further includes Cu, Ag, Pd, an Ag—Pd alloy, andAu.
 9. The method of manufacturing an electronic component according toclaim 7, wherein each of the plurality of internal electrodes furtherincludes a plurality of dielectric particles.
 10. The method ofmanufacturing an electronic component according to claim 1, wherein eachof the plurality of dielectric layers includes a plurality ofcrystalline particles each including Ba and Ti.
 11. The method ofmanufacturing an electronic component according to claim 1, wherein theplurality of internal electrodes include at least a first internalelectrode and a second internal electrode; the first internal electrodeextends to the first end surface of the multilayer body and is exposedat each of the first side surface and the second side surface of themultilayer body; and the second internal electrode extends to the secondend surface of the multilayer body and is exposed at each of the firstside surface and the second side surface of the multilayer body.
 12. Themethod of manufacturing an electronic component according to claim 1,further comprising a step of forming a first external electrode and asecond external electrode.
 13. The method of manufacturing an electroniccomponent according to claim 12, wherein the first external electrodecovers an entire or substantially an entire surface of the first endsurface of the multilayer body; and the second external electrode coversan entire or substantially an entire surface of the second end surfaceof the multilayer body.
 14. The method of manufacturing an electroniccomponent according to claim 12, wherein the plurality of internalelectrodes include at least a first internal electrode and a secondinternal electrode; the first external electrode is electricallyconnected to the first internal electrode; and the second externalelectrode is electrically connected to the second internal electrode.15. The method of manufacturing an electronic component according toclaim 12, wherein the first external electrode and the second externalelectrode each include an underlying electrode layer and a plated layerthat is provided on the underlying electrode layer.